The Tampa Bay Seawater Desalination
Plant is fully operational, providing the Tampa Bay region with up
to 25 million gallons per day (mgd) of drinking water. The plant is
the nation's largest seawater desalination facility.

When operating at full capacity, the
plant provides about 10 percent of the Tampa Bay region’s drinking
water supply. The plant is operated by American Water and Acciona
Agua, through their joint venture subsidiary American Water-Pridesa.

In December 2007, the plant
successfully completed and passed its performance test, marking the
end of remediation and the beginning of full operational status for
the nation’s largest seawater desalination facility.

During remediation, multiple
corrections were made to the pretreatment, reverse osmosis and post
treatment systems. Overhauling the pretreatment system was
required as the original system was not rigorous enough to filter
particles out of the seawater, which caused the plant's cartridge
filters and desalinating membranes to clog too quickly. Plant
remediation included:

The
addition of screens to remove incoming debris from source
water.

The
addition of a variable speed capability cooling water pump, which
enables water temperatures at the intake to be
maintained.

A
rapid mixing of treatment chemicals and conditioning prior to
filtration, which causes suspended solids to clump making them
easier to remove.

Converting the Dyna Sand filtration system from dual
stage to single stage.

The
addition of diatomaceous earth filters to further clean the
seawater after it has gone through coagulation, flocculation and
sand filtration.

A
redesigned reverse osmosis membrane cleaning system, which will
provide more effective cleaning of the membranes after use and
extend membrane
life.